Linux usb转串口驱动
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Linux USB转串口驱动程序:
/*
* USB Serial Converter driver
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/moduleparam.h>
#include <linux/seq_file.h>
#include <linux/spinlock.h>
#include <linux/mutex.h>
#include <linux/list.h>
#include <linux/uaccess.h>
#include <linux/serial.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
#include <linux/kfifo.h>
#include <linux/kgdb.h>
#include "hcd.h"
#include "pl2303.h"
/*
* Version Information
*/
#define DRIVER_AUTHOR "Greg Kroah-Hartman, [email protected], http://www.kroah.com/linux/"
#define DRIVER_DESC "USB Serial Driver core"
/* Driver structure we register with the USB core */
static struct usb_driver usb_serial_driver = {
.name = "usbserial",
.probe = usb_serial_probe,
.disconnect = usb_serial_disconnect,
.suspend = usb_serial_suspend,
.resume = usb_serial_resume,
.no_dynamic_id = 1,
};
/* There is no MODULE_DEVICE_TABLE for usbserial.c. Instead
the MODULE_DEVICE_TABLE declarations in each serial driver
cause the "hotplug" program to pull in whatever module is necessary
via modprobe, and modprobe will load usbserial because the serial
drivers depend on it.
*/
static int debug;
/* initially all NULL */
static struct usb_serial *serial_table[SERIAL_TTY_MINORS];
static DEFINE_MUTEX(table_lock);
static LIST_HEAD(usb_serial_driver_list);
/*
* Look up the serial structure. If it is found and it hasn‘t been
* disconnected, return with its disc_mutex held and its refcount
* incremented. Otherwise return NULL.
*/
struct usb_serial *usb_serial_get_by_index(unsigned index)
{
struct usb_serial *serial;
mutex_lock(&table_lock);
serial = serial_table[index];
if (serial) {
mutex_lock(&serial->disc_mutex);
if (serial->disconnected) {
mutex_unlock(&serial->disc_mutex);
serial = NULL;
} else {
kref_get(&serial->kref);
}
}
mutex_unlock(&table_lock);
return serial;
}
static struct usb_serial *get_free_serial(struct usb_serial *serial,
int num_ports, unsigned int *minor)
{
unsigned int i, j;
int good_spot;
dbg("%s %d", __func__, num_ports);
*minor = 0;
mutex_lock(&table_lock);
for (i = 0; i < SERIAL_TTY_MINORS; ++i) {
if (serial_table[i])
continue;
good_spot = 1;
for (j = 1; j <= num_ports-1; ++j)
if ((i+j >= SERIAL_TTY_MINORS) || (serial_table[i+j])) {
good_spot = 0;
i += j;
break;
}
if (good_spot == 0)
continue;
*minor = i;
j = 0;
dbg("%s - minor base = %d", __func__, *minor);
for (i = *minor; (i < (*minor + num_ports)) && (i < SERIAL_TTY_MINORS); ++i) {
serial_table[i] = serial;
serial->port[j++]->number = i;
}
mutex_unlock(&table_lock);
return serial;
}
mutex_unlock(&table_lock);
return NULL;
}
static void return_serial(struct usb_serial *serial)
{
int i;
dbg("%s", __func__);
mutex_lock(&table_lock);
for (i = 0; i < serial->num_ports; ++i)
serial_table[serial->minor + i] = NULL;
mutex_unlock(&table_lock);
}
static void destroy_serial(struct kref *kref)
{
struct usb_serial *serial;
struct usb_serial_port *port;
int i;
serial = to_usb_serial(kref);
dbg("%s - %s", __func__, serial->type->description);
/* return the minor range that this device had */
if (serial->minor != SERIAL_TTY_NO_MINOR)
return_serial(serial);
if (serial->attached)
serial->type->release(serial);
/* Now that nothing is using the ports, they can be freed */
for (i = 0; i < serial->num_port_pointers; ++i) {
port = serial->port[i];
if (port) {
port->serial = NULL;
put_device(&port->dev);
}
}
usb_put_dev(serial->dev);
kfree(serial);
}
void usb_serial_put(struct usb_serial *serial)
{
kref_put(&serial->kref, destroy_serial);
}
/*****************************************************************************
* Driver tty interface functions
*****************************************************************************/
/**
* serial_install - install tty
* @driver: the driver (USB in our case)
* @tty: the tty being created
*
* Create the termios objects for this tty. We use the default
* USB serial settings but permit them to be overridden by
* serial->type->init_termios.
*
* This is the first place a new tty gets used. Hence this is where we
* acquire references to the usb_serial structure and the driver module,
* where we store a pointer to the port, and where we do an autoresume.
* All these actions are reversed in serial_cleanup().
*/
static int serial_install(struct tty_driver *driver, struct tty_struct *tty)
{
int idx = tty->index;
struct usb_serial *serial;
struct usb_serial_port *port;
int retval = -ENODEV;
dbg("%s", __func__);
serial = usb_serial_get_by_index(idx);
if (!serial)
return retval;
port = serial->port[idx - serial->minor];
if (!port)
goto error_no_port;
if (!try_module_get(serial->type->driver.owner))
goto error_module_get;
/* perform the standard setup */
retval = tty_init_termios(tty);
if (retval)
goto error_init_termios;
retval = usb_autopm_get_interface(serial->interface);
if (retval)
goto error_get_interface;
mutex_unlock(&serial->disc_mutex);
/* allow the driver to update the settings */
if (serial->type->init_termios)
serial->type->init_termios(tty);
tty->driver_data = port;
/* Final install (we use the default method) */
tty_driver_kref_get(driver);
tty->count++;
driver->ttys[idx] = tty;
return retval;
error_get_interface:
error_init_termios:
module_put(serial->type->driver.owner);
error_module_get:
error_no_port:
usb_serial_put(serial);
mutex_unlock(&serial->disc_mutex);
return retval;
}
static int serial_activate(struct tty_port *tport, struct tty_struct *tty)
{
struct usb_serial_port *port =
container_of(tport, struct usb_serial_port, port);
struct usb_serial *serial = port->serial;
int retval;
mutex_lock(&serial->disc_mutex);
if (serial->disconnected)
retval = -ENODEV;
else
retval = port->serial->type->open(tty, port);
mutex_unlock(&serial->disc_mutex);
return retval;
}
static int serial_open(struct tty_struct *tty, struct file *filp)
{
struct usb_serial_port *port = tty->driver_data;
dbg("%s - port %d", __func__, port->number);
return tty_port_open(&port->port, tty, filp);
}
/**
* serial_down - shut down hardware
* @tport: tty port to shut down
*
* Shut down a USB serial port unless it is the console. We never
* shut down the console hardware as it will always be in use. Serialized
* against activate by the tport mutex and kept to matching open/close pairs
* of calls by the ASYNCB_INITIALIZED flag.
*/
static void serial_down(struct tty_port *tport)
{
struct usb_serial_port *port =
container_of(tport, struct usb_serial_port, port);
struct usb_serial_driver *drv = port->serial->type;
/*
* The console is magical. Do not hang up the console hardware
* or there will be tears.
*/
if (port->port.console)
return;
if (drv->close)
drv->close(port);
}
static void serial_hangup(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
dbg("%s - port %d", __func__, port->number);
tty_port_hangup(&port->port);
}
static void serial_close(struct tty_struct *tty, struct file *filp)
{
struct usb_serial_port *port = tty->driver_data;
dbg("%s - port %d", __func__, port->number);
tty_port_close(&port->port, tty, filp);
}
/**
* serial_cleanup - free resources post close/hangup
* @port: port to free up
*
* Do the resource freeing and refcount dropping for the port.
* Avoid freeing the console.
*
* Called asynchronously after the last tty kref is dropped,
* and the tty layer has already done the tty_shutdown(tty);
*/
static void serial_cleanup(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
struct usb_serial *serial;
struct module *owner;
/* The console is magical. Do not hang up the console hardware
* or there will be tears.
*/
if (port->port.console)
return;
dbg("%s - port %d", __func__, port->number);
tty->driver_data = NULL;
serial = port->serial;
owner = serial->type->driver.owner;
mutex_lock(&serial->disc_mutex);
if (!serial->disconnected)
usb_autopm_put_interface(serial->interface);
mutex_unlock(&serial->disc_mutex);
usb_serial_put(serial);
module_put(owner);
}
static int serial_write(struct tty_struct *tty, const unsigned char *buf,
int count)
{
struct usb_serial_port *port = tty->driver_data;
int retval = -ENODEV;
if (port->serial->dev->state == USB_STATE_NOTATTACHED)
goto exit;
dbg("%s - port %d, %d byte(s)", __func__, port->number, count);
/* pass on to the driver specific version of this function */
retval = port->serial->type->write(tty, port, buf, count);
exit:
return retval;
}
static int serial_write_room(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
dbg("%s - port %d", __func__, port->number);
/* pass on to the driver specific version of this function */
return port->serial->type->write_room(tty);
}
static int serial_chars_in_buffer(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
dbg("%s - port %d", __func__, port->number);
/* if the device was unplugged then any remaining characters
fell out of the connector ;) */
if (port->serial->disconnected)
return 0;
/* pass on to the driver specific version of this function */
return port->serial->type->chars_in_buffer(tty);
}
static void serial_throttle(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
dbg("%s - port %d", __func__, port->number);
/* pass on to the driver specific version of this function */
if (port->serial->type->throttle)
port->serial->type->throttle(tty);
}
static void serial_unthrottle(struct tty_struct *tty)
{
struct usb_serial_port *port = tty->driver_data;
dbg("%s - port %d", __func__, port->number);
/* pass on to the driver specific version of this function */
if (port->serial->type->unthrottle)
port->serial->type->unthrottle(tty);
}
static int serial_ioctl(struct tty_struct *tty, struct file *file,
unsigned int cmd, unsigned long arg)
{
struct usb_serial_port *port = tty->driver_data;
int retval = -ENODEV;
dbg("%s - port %d, cmd 0x%.4x", __func__, port->number, cmd);
/* pass on to the driver specific version of this function
if it is available */
if (port->serial->type->ioctl) {
retval = port->serial->type->ioctl(tty, file, cmd, arg);
} else
retval = -ENOIOCTLCMD;
return retval;
}
static void serial_set_termios(struct tty_struct *tty, struct ktermios *old)
{
struct usb_serial_port *port = tty->driver_data;
dbg("%s - port %d", __func__, port->number);
/* pass on to the driver specific version of this function
if it is available */
if (port->serial->type->set_termios)
port->serial->type->set_termios(tty, port, old);
else
tty_termios_copy_hw(tty->termios, old);
}
static int serial_break(struct tty_struct *tty, int break_state)
{
struct usb_serial_port *port = tty->driver_data;
dbg("%s - port %d", __func__, port->number);
/* pass on to the driver specific version of this function
if it is available */
if (port->serial->type->break_ctl)
port->serial->type->break_ctl(tty, break_state);
return 0;
}
static int serial_proc_show(struct seq_file *m, void *v)
{
struct usb_serial *serial;
int i;
char tmp[40];
dbg("%s", __func__);
seq_puts(m, "usbserinfo:1.0 driver:2.0\n");
for (i = 0; i < SERIAL_TTY_MINORS; ++i) {
serial = usb_serial_get_by_index(i);
if (serial == NULL)
continue;
seq_printf(m, "%d:", i);
if (serial->type->driver.owner)
seq_printf(m, " module:%s",
module_name(serial->type->driver.owner));
seq_printf(m, " name:\"%s\"",
serial->type->description);
seq_printf(m, " vendor:%04x product:%04x",
le16_to_cpu(serial->dev->descriptor.idVendor),
le16_to_cpu(serial->dev->descriptor.idProduct));
seq_printf(m, " num_ports:%d", serial->num_ports);
seq_printf(m, " port:%d", i - serial->minor + 1);
usb_make_path(serial->dev, tmp, sizeof(tmp));
seq_printf(m, " path:%s", tmp);
seq_putc(m, ‘\n‘);
usb_serial_put(serial);
mutex_unlock(&serial->disc_mutex);
}
return 0;
}
static int serial_proc_open(struct inode *inode, struct file *file)
{
return single_open(file, serial_proc_show, NULL);
}
static const struct file_operations serial_proc_fops = {
.owner = THIS_MODULE,
.open = serial_proc_open,
.read = seq_read,
.llseek = seq_lseek,
.release = single_release,
};
static int serial_tiocmget(struct tty_struct *tty, struct file *file)
{
struct usb_serial_port *port = tty->driver_data;
dbg("%s - port %d", __func__, port->number);
if (port->serial->type->tiocmget)
return port->serial->type->tiocmget(tty, file);
return -EINVAL;
}
static int serial_tiocmset(struct tty_struct *tty, struct file *file,
unsigned int set, unsigned int clear)
{
struct usb_serial_port *port = tty->driver_data;
dbg("%s - port %d", __func__, port->number);
if (port->serial->type->tiocmset)
return port->serial->type->tiocmset(tty, file, set, clear);
return -EINVAL;
}
/*
* We would be calling tty_wakeup here, but unfortunately some line
* disciplines have an annoying habit of calling tty->write from
* the write wakeup callback (e.g. n_hdlc.c).
*/
void usb_serial_port_softint(struct usb_serial_port *port)
{
schedule_work(&port->work);
}
EXPORT_SYMBOL_GPL(usb_serial_port_softint);
static void usb_serial_port_work(struct work_struct *work)
{
struct usb_serial_port *port =
container_of(work, struct usb_serial_port, work);
struct tty_struct *tty;
dbg("%s - port %d", __func__, port->number);
tty = tty_port_tty_get(&port->port);
if (!tty)
return;
tty_wakeup(tty);
tty_kref_put(tty);
}
static void kill_traffic(struct usb_serial_port *port)
{
usb_kill_urb(port->read_urb);
usb_kill_urb(port->write_urb);
/*
* This is tricky.
* Some drivers submit the read_urb in the
* handler for the write_urb or vice versa
* this order determines the order in which
* usb_kill_urb() must be used to reliably
* kill the URBs. As it is unknown here,
* both orders must be used in turn.
* The call below is not redundant.
*/
usb_kill_urb(port->read_urb);
usb_kill_urb(port->interrupt_in_urb);
usb_kill_urb(port->interrupt_out_urb);
}
static void port_release(struct device *dev)
{
struct usb_serial_port *port = to_usb_serial_port(dev);
dbg ("%s - %s", __func__, dev_name(dev));
/*
* Stop all the traffic before cancelling the work, so that
* nobody will restart it by calling usb_serial_port_softint.
*/
kill_traffic(port);
cancel_work_sync(&port->work);
usb_free_urb(port->read_urb);
usb_free_urb(port->write_urb);
usb_free_urb(port->interrupt_in_urb);
usb_free_urb(port->interrupt_out_urb);
kfifo_free(&port->write_fifo);
kfree(port->bulk_in_buffer);
kfree(port->bulk_out_buffer);
kfree(port->interrupt_in_buffer);
kfree(port->interrupt_out_buffer);
kfree(port);
}
static struct usb_serial *create_serial(struct usb_device *dev,
struct usb_interface *interface,
struct usb_serial_driver *driver)
{
struct usb_serial *serial;
serial = kzalloc(sizeof(*serial), GFP_KERNEL);
if (!serial) {
dev_err(&dev->dev, "%s - out of memory\n", __func__);
return NULL;
}
serial->dev = usb_get_dev(dev);
serial->type = driver;
serial->interface = interface;
kref_init(&serial->kref);
mutex_init(&serial->disc_mutex);
serial->minor = SERIAL_TTY_NO_MINOR;
return serial;
}
static const struct usb_device_id *match_dynamic_id(struct usb_interface *intf,
struct usb_serial_driver *drv)
{
struct usb_dynid *dynid;
spin_lock(&drv->dynids.lock);
list_for_each_entry(dynid, &drv->dynids.list, node) {
if (usb_match_one_id(intf, &dynid->id)) {
spin_unlock(&drv->dynids.lock);
return &dynid->id;
}
}
spin_unlock(&drv->dynids.lock);
return NULL;
}
static const struct usb_device_id *get_iface_id(struct usb_serial_driver *drv,
struct usb_interface *intf)
{
const struct usb_device_id *id;
id = usb_match_id(intf, drv->id_table);
if (id) {
dbg("static descriptor matches");
goto exit;
}
id = match_dynamic_id(intf, drv);
if (id)
dbg("dynamic descriptor matches");
exit:
return id;
}
static struct usb_serial_driver *search_serial_device(
struct usb_interface *iface)
{
const struct usb_device_id *id;
struct usb_serial_driver *drv;
/* Check if the usb id matches a known device */
list_for_each_entry(drv, &usb_serial_driver_list, driver_list) {
id = get_iface_id(drv, iface);
if (id)
return drv;
}
return NULL;
}
static int serial_carrier_raised(struct tty_port *port)
{
struct usb_serial_port *p = container_of(port, struct usb_serial_port, port);
struct usb_serial_driver *drv = p->serial->type;
if (drv->carrier_raised)
return drv->carrier_raised(p);
/* No carrier control - don‘t block */
return 1;
}
static void serial_dtr_rts(struct tty_port *port, int on)
{
struct usb_serial_port *p = container_of(port, struct usb_serial_port, port);
struct usb_serial_driver *drv = p->serial->type;
if (drv->dtr_rts)
drv->dtr_rts(p, on);
}
static const struct tty_port_operations serial_port_ops = {
.carrier_raised = serial_carrier_raised,
.dtr_rts = serial_dtr_rts,
.activate = serial_activate,
.shutdown = serial_down,
};
int usb_serial_probe(struct usb_interface *interface,
const struct usb_device_id *id)
{
struct usb_device *dev = interface_to_usbdev(interface);
struct usb_serial *serial = NULL;
struct usb_serial_port *port;
struct usb_host_interface *iface_desc;
struct usb_endpoint_descriptor *endpoint;
struct usb_endpoint_descriptor *interrupt_in_endpoint[MAX_NUM_PORTS];
struct usb_endpoint_descriptor *interrupt_out_endpoint[MAX_NUM_PORTS];
struct usb_endpoint_descriptor *bulk_in_endpoint[MAX_NUM_PORTS];
struct usb_endpoint_descriptor *bulk_out_endpoint[MAX_NUM_PORTS];
struct usb_serial_driver *type = NULL;
int retval;
unsigned int minor;
int buffer_size;
int i;
int num_interrupt_in = 0;
int num_interrupt_out = 0;
int num_bulk_in = 0;
int num_bulk_out = 0;
int num_ports = 0;
int max_endpoints;
lock_kernel(); /* guard against unloading a serial driver module */
type = search_serial_device(interface);
if (!type) {
unlock_kernel();
dbg("none matched");
return -ENODEV;
}
serial = create_serial(dev, interface, type);
if (!serial) {
unlock_kernel();
dev_err(&interface->dev, "%s - out of memory\n", __func__);
return -ENOMEM;
}
/* if this device type has a probe function, call it */
if (type->probe) {
const struct usb_device_id *id;
if (!try_module_get(type->driver.owner)) {
unlock_kernel();
dev_err(&interface->dev,
"module get failed, exiting\n");
kfree(serial);
return -EIO;
}
id = get_iface_id(type, interface);
retval = type->probe(serial, id);
module_put(type->driver.owner);
if (retval) {
unlock_kernel();
dbg("sub driver rejected device");
kfree(serial);
return retval;
}
}
/* descriptor matches, let‘s find the endpoints needed */
/* check out the endpoints */
iface_desc = interface->cur_altsetting;
for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
endpoint = &iface_desc->endpoint[i].desc;
if (usb_endpoint_is_bulk_in(endpoint)) {
/* we found a bulk in endpoint */
dbg("found bulk in on endpoint %d", i);
bulk_in_endpoint[num_bulk_in] = endpoint;
++num_bulk_in;
}
if (usb_endpoint_is_bulk_out(endpoint)) {
/* we found a bulk out endpoint */
dbg("found bulk out on endpoint %d", i);
bulk_out_endpoint[num_bulk_out] = endpoint;
++num_bulk_out;
}
if (usb_endpoint_is_int_in(endpoint)) {
/* we found a interrupt in endpoint */
dbg("found interrupt in on endpoint %d", i);
interrupt_in_endpoint[num_interrupt_in] = endpoint;
++num_interrupt_in;
}
if (usb_endpoint_is_int_out(endpoint)) {
/* we found an interrupt out endpoint */
dbg("found interrupt out on endpoint %d", i);
interrupt_out_endpoint[num_interrupt_out] = endpoint;
++num_interrupt_out;
}
}
#if defined(CONFIG_USB_SERIAL_PL2303) || defined(CONFIG_USB_SERIAL_PL2303_MODULE)
/* BEGIN HORRIBLE HACK FOR PL2303 */
/* this is needed due to the looney way its endpoints are set up */
if (((le16_to_cpu(dev->descriptor.idVendor) == PL2303_VENDOR_ID) &&
(le16_to_cpu(dev->descriptor.idProduct) == PL2303_PRODUCT_ID)) ||
((le16_to_cpu(dev->descriptor.idVendor) == ATEN_VENDOR_ID) &&
(le16_to_cpu(dev->descriptor.idProduct) == ATEN_PRODUCT_ID)) ||
((le16_to_cpu(dev->descriptor.idVendor) == ALCOR_VENDOR_ID) &&
(le16_to_cpu(dev->descriptor.idProduct) == ALCOR_PRODUCT_ID)) ||
((le16_to_cpu(dev->descriptor.idVendor) == SIEMENS_VENDOR_ID) &&
(le16_to_cpu(dev->descriptor.idProduct) == SIEMENS_PRODUCT_ID_EF81))) {
if (interface != dev->actconfig->interface[0]) {
/* check out the endpoints of the other interface*/
iface_desc = dev->actconfig->interface[0]->cur_altsetting;
for (i = 0; i < iface_desc->desc.bNumEndpoints; ++i) {
endpoint = &iface_desc->endpoint[i].desc;
if (usb_endpoint_is_int_in(endpoint)) {
/* we found a interrupt in endpoint */
dbg("found interrupt in for Prolific device on separate interface");
interrupt_in_endpoint[num_interrupt_in] = endpoint;
++num_interrupt_in;
}
}
}
/* Now make sure the PL-2303 is configured correctly.
* If not, give up now and hope this hack will work
* properly during a later invocation of usb_serial_probe
*/
if (num_bulk_in == 0 || num_bulk_out == 0) {
unlock_kernel();
dev_info(&interface->dev, "PL-2303 hack: descriptors matched but endpoints did not\n");
kfree(serial);
return -ENODEV;
}
}
/* END HORRIBLE HACK FOR PL2303 */
#endif
#ifdef CONFIG_USB_SERIAL_GENERIC
if (type == &usb_serial_generic_device) {
num_ports = num_bulk_out;
if (num_ports == 0) {
unlock_kernel();
dev_err(&interface->dev,
"Generic device with no bulk out, not allowed.\n");
kfree(serial);
return -EIO;
}
}
#endif
if (!num_ports) {
/* if this device type has a calc_num_ports function, call it */
if (type->calc_num_ports) {
if (!try_module_get(type->driver.owner)) {
unlock_kernel();
dev_err(&interface->dev,
"module get failed, exiting\n");
kfree(serial);
return -EIO;
}
num_ports = type->calc_num_ports(serial);
module_put(type->driver.owner);
}
if (!num_ports)
num_ports = type->num_ports;
}
serial->num_ports = num_ports;
serial->num_bulk_in = num_bulk_in;
serial->num_bulk_out = num_bulk_out;
serial->num_interrupt_in = num_interrupt_in;
serial->num_interrupt_out = num_interrupt_out;
/* found all that we need */
dev_info(&interface->dev, "%s converter detected\n",
type->description);
/* create our ports, we need as many as the max endpoints */
/* we don‘t use num_ports here because some devices have more
endpoint pairs than ports */
max_endpoints = max(num_bulk_in, num_bulk_out);
max_endpoints = max(max_endpoints, num_interrupt_in);
max_endpoints = max(max_endpoints, num_interrupt_out);
max_endpoints = max(max_endpoints, (int)serial->num_ports);
serial->num_port_pointers = max_endpoints;
unlock_kernel();
dbg("%s - setting up %d port structures for this device",
__func__, max_endpoints);
for (i = 0; i < max_endpoints; ++i) {
port = kzalloc(sizeof(struct usb_serial_port), GFP_KERNEL);
if (!port)
goto probe_error;
tty_port_init(&port->port);
port->port.ops = &serial_port_ops;
port->serial = serial;
spin_lock_init(&port->lock);
/* Keep this for private driver use for the moment but
should probably go away */
INIT_WORK(&port->work, usb_serial_port_work);
serial->port[i] = port;
port->dev.parent = &interface->dev;
port->dev.driver = NULL;
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